From: Dave Martin Dave.Martin@arm.com
maillist inclusion category: feature bugzilla: 46790 CVE: NA
Reference: https://github.com/norov/linux/commits/ilp32-5.2
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ILP32 uses the same struct sigcontext as the native ABI (i.e., LP64), but a different layout for the rest of the signal frame (since siginfo_t and ucontext_t are both ABI-dependent).
Since the purpose of parse_user_sigframe() is really to parse sigcontext and not the whole signal frame, the function does not need to depend on the layout of rt_sigframe -- the only purpose of the rt_sigframe pointer is for use as a base to measure the signal frame size.
So, this patch renames the function to make it clear that only the sigcontext is really being parsed, and makes the sigframe base pointer generic. A macro is defined to provide a suitable duck-typed interface that can be used with both sigframe definitions.
Suggested-by: Yury Norov ynorov@caviumnetworks.com Signed-off-by: Dave Martin Dave.Martin@arm.com Signed-off-by: Yury Norov ynorov@caviumnetworks.com Signed-off-by: Yury Norov ynorov@marvell.com Signed-off-by: Xiongfeng Wang wangxiongfeng2@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com Signed-off-by: Chen Jun chenjun102@huawei.com
Conflicts: arch/arm64/kernel/signal.c
Signed-off-by: Chen Jiahao chenjiahao16@huawei.com --- arch/arm64/kernel/signal.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index 2cfc810d0a5b..a56fe9076990 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -573,16 +573,16 @@ extern int restore_zt_context(struct user_ctxs *user);
#endif /* ! CONFIG_ARM64_SME */
-static int parse_user_sigframe(struct user_ctxs *user, - struct rt_sigframe __user *sf) +static int __parse_user_sigcontext(struct user_ctxs *user, + struct sigcontext __user const *sc, + void __user const *sigframe_base) { - struct sigcontext __user *const sc = &sf->uc.uc_mcontext; struct _aarch64_ctx __user *head; char __user *base = (char __user *)&sc->__reserved; size_t offset = 0; size_t limit = sizeof(sc->__reserved); bool have_extra_context = false; - char const __user *const sfp = (char const __user *)sf; + char const __user *const sfp = (char const __user *)sigframe_base;
user->fpsimd = NULL; user->sve = NULL; @@ -765,6 +765,9 @@ static int parse_user_sigframe(struct user_ctxs *user, return -EINVAL; }
+#define parse_user_sigcontext(user, sf) \ + __parse_user_sigcontext(user, &(sf)->uc.uc_mcontext, sf) + static int restore_sigframe(struct pt_regs *regs, struct rt_sigframe __user *sf) { @@ -790,7 +793,7 @@ static int restore_sigframe(struct pt_regs *regs,
err |= !valid_user_regs(®s->user_regs, current); if (err == 0) - err = parse_user_sigframe(&user, sf); + err = parse_user_sigcontext(&user, sf);
if (err == 0 && system_supports_fpsimd()) { if (!user.fpsimd)